According to George Crump, founder of analyst firm Storage Switzerland, the choice comes down to whether it is more important for a given environment to have less latency or less hardware to maintain locally. With an all-cloud environment, administrators don't have to worry about monitoring hardware on site, but users will experience more latency compared to a hybrid cloud deployment.
That's why the vast majority of cloud deployments use a hybrid approach, Crump told storage professionals during a presentation at a TechTarget Storage Decisions seminar. "The hybrid approach is significantly more common," he said. "There's some sort of intermediary device that you install in your data center. You probably have the responsibility to manage and keep it maintained, and then it does conversion to some cloud vendor."
Crump went on to explain several types of hybrid configurations and use cases. Appliances in a hybrid cloud deployment are typically block storage based and use iSCSI or Fibre Channel connections. File-sharing types of appliances use CFS or NFS. Backup, he said, is the No. 1 use case for hybrid clouds. "Almost every backup solution that we track has added some form of cloud functionality. Some have done a very good job of integration where the move to the cloud is basically seamless," he noted. "In many cases, [appliance vendors] don’t even give you an option of picking your cloud vendor."
In a file-sharing type of implementation, Crump said the cloud acts more like a cache. "We've seen several that are all solid-state on premises, and then they cache to the cloud," he said.
He also described another hybrid approach that's catching on: gateways or controllers. However, he urged users to be cautious of this option because it "really isn't integrated into the actual application. It's just another appliance or piece of software you buy that does the translation. That tends to not be as clean."